High resolution stalagmite δ^(18)O records over the past 1000 years from Dongge Cave in Guizhou

Based on MC-ICP-MS U-series dating and stable O-isotope analysis results, a 4―5 years resolution monsoon record over the past 1000 years has been estab- lished for two stalagmites from Dongge Cave, Guizhou. The high resolution oxygen isotope record serves as a proxy for variations in rainfall of Asian southwest monsoon over the Yunnan-Guizhou Plateau. A close relation of the δ 18O record with the ?14C record from tree rings largely reflects impact of centennial-scale solar activity on the monsoon climate changes. The conspicuous decrease in the δ 18O value at AD 1720 indicates an abrupt increase in monsoon rainfall, sug- gesting that an atmospheric-oceanic couple over the tropical Indian Ocean plays an important role in rapid increase of the Northern Hemisphere temperature over the last century.

Based on MC-ICP-MS U-series dating and stable O-isotope analysis results, a4-5 years resolution monsoon record over the past 1000 years has been established for twostalagmites from Dongge Cave, Guizhou. The high resolution oxygen isotope record serves as a proxyfor variations in rainfall of Asian southwest monsoon over the Yunnan-Guizhou Plateau. A closerelation of the delta^(18)O record with the triangle open ^(14)C record from tree rings largelyreflects impact of centennial-scale solar activity on the monsoon climate changes. The conspicuousdecrease in the delta^(18)O value at AD 1720 indicates an abrupt increase in monsoon rainfall,suggesting that an atmospheric-oceanic couple over the tropical Indian Ocean plays an important rolein rapid increase of the Northern Hemisphere temperature over the last century.